It’s a bug that impacts most of the Internet. Heartbleed could give hackers access to user passwords and even trick people into using fake versions of popular Web sites.

Security engineers at Codenomicon who found the bug, are reporting that the vulnerability is in the OpenSSL cryptographic software library. The weakness, they said, steals information typically protected by the SSL/TLS encryption used to secure the Internet.

We caught up with Martin Gallo, a senior security consultant at security software firm Core Security, to get his take on the Heartbleed fallout. He told us the extent of the problem is two-fold. On one hand, he said, companies running services that rely in any way on OpenSSL may have been affected for the past two years because OpenSSL is the main security technology for most sites running services.

“On the other hand, the issue also affects the client-side of SSL connections using the library. This includes also a large range of end-user software that might be vulnerable,” Gallo said. “Another interesting question is to what extent commercial software makes use of this flawed library or routines.”

That of course, remains to be seen. Right now, IT admins may be scrambling for an action plan they can take to cover the known bases. Gallo recommends three: (1) install new code and patches; (2) work with certificate authorities as SSL private keys may have been compromised; and (3) alert customers and users regarding the client SSL software.

Not Easy to Patch

In terms of installing new code and patches, there are plenty of challenges at hand. One of the key obstacles, Gallo explained, is that OpenSSL is typically found in systems that are not easy to patch, such as embedded or network devices.

“Ensuring that all services are running updated versions is a very demanding task,” Gallo said. “Additionally, system administrators must be sure to also deploy patches on the workstations and end-user software.”

But that’s not the only challenge. Gallo pointed out another: All the SSL/TLS server certificates on affected hosts should be considered as potentially compromised. Renewal and deployment of all affected certificates on big enterprises is a very difficult task to conduct and needs a lot of coordinated work and awareness, he said.

Cost of Patching Heartbleed

How much will this cost enterprises? Heartbleed-associated expenses run the gamut from patching servers and workstations to issuing and deploying new certificates.

At the end of the day, Gallo said a bug like Heartbleed makes a strong case for using SSL/TLS Perfect Forward Secrecy cipher suites because exploiting this vulnerability to get access to the server's private certificates could render previously eavesdropped connections wide open to the attacker's eyes.

“We usually find companies asking why they should test the security of a service that runs on top of SSL/TLS if it is already protected,” he concluded. “The concept of defense in depth is usually one of the answers, what if SSL/TLS is compromised.”